Zhenhua Xu

University of Toronto | U of T · Department of Cell and Systems Biology

Background and AimsMicroRNAs (miRNAs) play an important role in the responses and adaptation of plants to many stresses including low nitrogen (LN). Characterizing relevant miRNAs will improve our understanding of nitrogen (N) use efficiency and LN tolerance and thus contribute to sustainable maize production. The objective of this study was to ide...

Chloroplast biogenesis has been well documented in higher plants, yet the complex methods used to regulate chloroplast activity under fluctuating environmental conditions are not well understood. In rice (Oryza sativa), the CYTOKININ-RESPONSIVE GATA TRANSCRIPTION FACTOR 1 (Cga1) shows increased expression following light, nitrogen and cytokinin tre...

Nitrate is the major source of nitrogen available for many crop plants and is often the limiting factor for plant growth and agricultural productivity especially for maize. Many studies have been done identifying the transcriptome changes under low nitrate conditions. However, the microRNAs (miRNAs) varied under nitrate limiting conditions in maize...

Strigolactones (SLs) regulate many aspects of plant development, but ambiguities remain about how this hormone is perceived because SL-complexed receptor structures do not exist. We find that when SL binds the Striga receptor, ShHTL5, a series of conformational changes relative to the unbound state occur, but these events are not sufficient for sig...

Deciphering signalling pathways is essential to understanding how organisms respond to environmental cues but elucidating how these signalling pathways evolve in new environments is less clear. 1,2 Most plants, for example, monitor multiple environmental cues to optimize the time and place to germinate. Some root parasitic plants, however, germinat...

Significance Parasitic plants like witchweed cause huge losses in crop yield in Africa. A key part to the success of witchweed is to start its life cycle upon sensing small molecules called strigolactones, which are exuded from roots of host plants into the soil. Witchweed sense host-derived strigolactones through receptors called HTLs. It is thoug...

Parasitic plant infestations dramatically reduce the yield of many major food crops of sub-Saharan Africa and pose a serious threat to food security on that continent1. The first committed step of a successful infestation is the germination of parasite seeds primarily in response to a group of related small-molecule hormones called strigolactones (...

Anthocyanins are water-soluble pigments with antioxidant activities. In plants, multiple factors can trigger the accumulation of anthocyanins, including chemicals and environmental factors. Reactive oxygen species (ROS) are common by-products produced under different biotic and abiotic conditions and cause oxidative stress when accumulated at a hig...

GATA transcription factors are involved in multiple processes in plant growth and development. Two GATA factors, NITRATE-INDUCIBLE, CARBON METABOLISM-INVOLVED (GNC) and CYTOKININ-RESPONSIVE GATA FACTOR 1 (CGA1, also named GNL), are important regulators in greening, flowering, senescence, and hormone signaling. However, their direct target genes rel...

Anthocyanins are known to have antioxidant activities. Their accumulation can be triggered by many chemical and environmental factors, including reactive oxygen species (ROS). However, the mechanism of ROS-induced anthocyanin accumulation and the role of anthocyanins in the response of Arabidopsis (Arabidopsis thaliana) to different stresses are la...

Production of anthocyanins is one of the adaptive responses employed by plants during stress conditions. During stress, anthocyanin biosynthesis is mainly regulated at the transcriptional level via a complex interplay between activators and repressors of anthocyanin biosynthesis genes. In this study, we investigated the role of a NAC transcription...

World-wide crop production is significantly affected by various abiotic and biotic stresses. Research on plant stress signalling and the resulting physiological response can provide insights into the development of crop cultivars with improved stress tolerance. In the current work, the role of anthocyanins in plant response to reactive oxygen speci...